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Comparison of the Yield of Very Low Nicotine Content Cigarettes to the Top 100 United States Brand Styles

Summary

The objective of this work was to compare the nicotine content and yield of new very low nicotine content cigarettes (VLN™) to the top 100 cigarette brand styles in the United States. Nicotine in tobacco filler and nicotine in smoke were measured. On a dry weight basis, VLN™ cigarettes averaged 0.5 mg of nicotine/g tobacco as compared to 19.4 for the top 100 brand styles in the United States. On a cigarette basis, VLN™ cigarettes contained 0.27 mg of nicotine compared to 12 mg for the top brands. On an ISO smoke yield basis, VLN™ produced 0.03 mg nicotine/cig compared to 0.903 mg nicotine/cig for the leading brands. VLN™ cigarettes contained > 95% less nicotine on a per gram basis of tobacco or per cigarette basis than the top 100 brand styles in the U.S. VLN™ cigarettes yielded > 95% less nicotine in smoke than the top brand styles in the United States.

Open access
Effects of Varying Tobacco Rod Circumference on Cigarette Combustion: An Experimental Investigation

Summary

To study the effects of tobacco rod circumference on cigarette combustion status, cigarettes were made with three different circumferences of 24 mm, 20 mm, 17 mm and otherwise identical construction. Their combustion characteristics, including combustion coal volume, characteristic temperature distribution, heating rate, instantaneous burn rate, and yields of selected mainstream smoke chemicals, were systematically measured. The results indicated that the cigarettes with the lowest circumference of 17 mm showed higher combustion temperatures with a smaller coal volume. The maximum instantaneous burn rate was distinctly different for the three cigarettes, from 1.84 mm/s to 2.48 mm/s, when their circumference was reduced from 24 mm to 17 mm. The tobacco mass consumption per puff showed a negative trend when the circumference decreased. The majority of the chemical compounds (16 of 21) measured in mainstream smoke decreased when the circumference was reduced, except for formaldehyde, while the yields of the chemical compounds produced per weight of cut tobacco, consumed during puffing, showed an obverse trend.

Open access
Measurement Method of the Width of the Strands of Cut Tobacco Based on Digital Image Processing

Summary

The width of cut tobacco strands is an important indicator for physical parameters as well as for the smoking quality. In some countries, cut width helps to distinguish fine-cut tobacco and pipe tobacco and thus differentiates taxation rate. A new method for rapid measurement of the width of cut tobacco strands was developed based on digital image processing, because the method described in ISO 20193, though easy to implement in factories, proved time consuming and generated high testing costs. The essence of this method is to determine the statistic width of incisions. The straight-line segments represent the width of strands of cut tobacco, from which the determination of the width for randomly placed tobacco strands could be achieved. Five kinds of samples (‘ISO collaborative study samples 0.4 mm, 1.0 mm, 1.6 mm and 3.0 mm’ and ‘Guangdong baked 0.9 mm’) were used to study the comparability of the measurement results between the method presented in this work and the current ISO method. Results show that accuracy and repeatability are comparable. In addition, the testing efficiency of the method presented in this work appears to be higher than the current ISO method, and it is thus a promising alternative method for measuring the width of strands of cut tobacco.

Open access
Optimal Synthesis of Substituted and Branched Pyrazines via Reaction of Alpha Hydroxy Ketones with Selected Nitrogen Sources

Summary

Employment of 1-hydroxy-acetone as a carbon source and NH4OH as a source of base and nitrogen, has enabled arrays of pyrazines to be synthesized. Reaction conditions such as temperature, time, carbon/nitrogen mole ratios and pH were optimized to maximize the quantity of pyrazines, thereby providing the synthesis of at least 19–20 structurally different pyrazines. Addition of amino acids, selected aldehydes, and hydrolyzed tobacco-derived F1 protein has positively impacted the array of pyrazines from both qualitative and quantitative aspects. Results further showed that by changing the carbon source from 1-hydroxy-acetone to 1-hydroxy-2-butanone and/or 2-hydroxy-3-butanone, control of the type of pyrazines being synthesized could be realized in that the qualitative and quantitative distributions of the pyrazine array were shifted to higher molecular weight derivatives. A relatively large scale reaction (1.5 L) employing optimized parameters yielded > 2 g of a diverse array of pyrazines dominated by multiple dimethylpyrazine derivatives. While systematically varying reaction conditions and reagent mole ratios can predictably alter the distribution and yield of pyrazines, the two most overwhelmingly significant factors governing these two pyrazine product characteristics included the structure of the carbon source and the presence or absence of aldehydes and free amino acids.

Open access
Comparison of Mainstream Smoke Composition from CR20 Resin Filter and Empty-Cavity Filter Cigarettes by Headspace SPME Coupled with GC×GC TOFMS and Chemometric Analysis

Summary

A previously established method based on headspace solidphase microextraction (HS-SPME) and comprehensive two-dimensional gas chromatography (GC×GC) coupled to time-of-flight mass spectrometry (TOFMS) has been used to evaluate and compare the profiles of semi-volatile compounds present in mainstream tobacco smoke particulate matter trapped on glass fibre filters for two types of cigarettes differing only in filter design. In the first cigarette, the filter cavity contained approximately 60 mg of a weakly basic macroporous polystyrene resin cross-linked with divinyl benzene and with surface amine functionality (CR20), whereas in the second cigarette, it was empty.

Relative quantitative analysis, chemical identification, and chemical grouping allowed the use of both parametric and non-parametric analyses to identify differences in the chemical composition of the smokes from these cigarettes. The analysis demonstrated that in addition to the selective partial removal of volatile carbonyls and HCN demonstrated previously, CR20 selectively, but incompletely removed 316 compounds from the particulate phase of cigarette smoke, mainly aryl and aromatic hydrocarbons as well as other more volatile species. In contrast, the relative proportion of amines, hydroxylated aromatic compounds and less volatile species was increased in the smoke from the cigarette containing CR20 in the filter.

Our findings show that high resolution GC techniques combined with mass spectrometry and chemometric approaches are powerful tools for deconvoluting the complexity of combustion aerosols, as well as helping to identify changes in chemical composition resulting from modifications to cigarette designs. [Beitr. Tabakforsch. Int. 28 (2019) 231–249]

Open access
Conditioning of Tobacco and Tobacco Products: The Effect of Forced Air Flow

Summary

Conditioning is a very important procedure for tobacco and tobacco products before their corresponding chemical and physical analysis. For cigarettes, forced air flow is generally required during the conditioning procedure. A special wind tunnel was designed to investigate how the forced air flow affects the conditioning of cigarettes in a constant climate laboratory. Two types of cigarettes with blended (including flue-cured and burley tobacco strands) and pure flue-cured tobacco strands were selected as test samples. It was found that the conditioning time to achieve the equilibrium could be shortened from 23 h without forced air flow to 7 h with a forced air flow rate of 2m/s. This is mainly due to the exchange of water molecules between cigarette samples and atmosphere being accelerated by applying the forced air flow. It was concluded that a 48 h conditioning period using the described forced air flow rate setup was unnecessary to attain the equilibrium for cigarettes. [Beitr. Tabakforsch. Int. 28 (2019) 224–229]

Open access
Extraction from Moist Snuff with Artificial Saliva of Benzo[a]pyrene and Other Polycyclic Aromatic Hydrocarbons

Summary

The present study evaluated in vitro extractability of various polycyclic aromatic hydrocarbons (PAHs) from moist snuff, when the extracting agent was water or artificial saliva. The extraction was performed on nine brands of moist snuff samples that are commercially available and were purchased from the market in January 2018. The moist snuff brands were selected to represent brands with different tobacco cut size descriptors and flavors. For the measurement of PAHs, two different analytical methods were used, an HPLC (High Performance Liquid Chromatography) method for measuring only benzo[a]pyrene (BaP) and a GC/MS/MS (Gas Chromatography Tandem Mass Spectrometry) method for measuring 21 PAHs (including BaP). These methods were modifications of preexistent methods reported in the literature. The results for BaP indicated that by extracting 500 mg of freeze-dried moist snuff with 6 portions of 20 mL water (120 mL), or with 4 portions of 20 mL artificial saliva, followed by two portions of 20 mL water, the BaP remains close to 100% in the solid material and it is not detected in the extracting solution. PAHs with a molecular weight similar or heavier than BaP also showed no extractability. Lighter PAHs such as fluorene, phenanthrene, anthracene, and 5-methylanthracene showed a relatively good extractability. An intermediate group including fluoranthene, pyrene, and benz[a]anthracene showed some extractability in the conditions of this in vitro experiment. This study is not a substitute for clinical studies regarding PAH uptake in human users of moist snuff. However, the results indicate very limited bioavailability of BaP and heavier PAHs from moist snuff. Higher, but variable bioavailability was indicated for lighter PAHs. Important implications of these findings are that: 1) measurably different BaP content of two moist snuff products is unlikely to result in any meaningfully different consumer exposure to BaP; and 2) biomarkers for one PAH cannot necessarily be used as a reliable indicator of exposure to another PAH, particularly if the molecular weights of the precursor PAHs differ since their bioavailabilities can be very different. [Beitr. Tabakforsch. Int. 28 (2019) 214–223]

Open access
LC-MS/MS Analysis of Sugars, Alditols, and Humectants in Smokeless Tobacco Products

Summary

Globally, smokeless tobacco (ST) includes a wide array of chemically diverse products generally used in the oral cavity. Although ST has been widely investigated, this study was undertaken to determine the levels of sugars (mono- and di-saccharides), alditols, and humectants present in major ST categories/subcategories by using high performance liquid chromatography coupled with a triple quadrupole mass spectrometer (HPLC-MS/MS). The products studied included chewing tobacco (loose leaf, plug, twist), US moist snuff, Swedish snus, creamy snuff, dry snuff, dissolvable tobacco products, and tobacco-coated toothpicks. The highest mean sugar level was detected in chewing tobacco (9.3–27.5%, w/w), followed by dissolvable tobacco (2.1%); all other products were lower than 1%. Creamy snuff had the highest mean alditol levels (22.6%), followed by dissolvable tobacco (15.4%); all others had levels lower than 1%. The detected mean humectant levels ranged from non-detectable to 5.9%. This study demonstrates the broad chemical diversity among ST. This research may aid researchers and public health advocates investigating the exposures and risks of ST. [Beitr. Tabakforsch. Int. 28 (2019) 203–213]

Open access
Determination of Humectants in Tobacco Filler by High Performance Chromatography/Single Quadrupole Mass Spectrometry

Summary

Glycerol, and 1,2-propylene glycol are the humectants most commonly used by the tobacco industry. They are found in a variety of tobacco products and are often present at high levels (~2–5 % w/w). While humectants are generally considered safe, they may serve as precursors in the formation of harmful carbonyl compounds. A selective, precise, and sensitive method for the quantification of several humectants in cigarette filler was developed. The method’s sample clean-up is a two-step process consisting of a mechanical extraction, followed by solid phase extraction. Individual humectants are separated, identified, and measured using liquid chromatography coupled to a single quadrupole mass spectrometer as the detector (LC/MS). Detection limits were 0.105, 0.575, and 0.039 mg/cigarette for glycerol, 1,2-propylene glycol and triethylene glycol, respectively. The quantification range for these analytes was 0.4–75.0 mg/cigarette. Twenty-seven brands of domestic commercial cigarettes were evaluated to assess typical levels of humectants in the tobacco filler.

Open access
Determination of Hydrogen Cyanide in Cigarette Smoke by Continuous Flow Analysis Method Using Safer Chemistry

Summary

A new safe and sensitive method to determine hydrogen cyanide (HCN) in cigarette smoke using continuous flow analyser (CFA) has been developed and validated. The use of highly toxic potassium cyanide (KCN) as a standard necessitates the development of a safer method for the determination of HCN in cigarette smoke. In this described method KCN is replaced by less toxic potassium tetracyanozincate (Lethal Dose LD50 oral is 7.49 mg/kg for KCN and 2000 mg/kg for potassium tetracyanozincate). Furthermore, the new method uses isonicotinic acid-barbituric acid (coupling reagent) instead of pyridine-pyrazolone as a reagent for the determination of HCN, and hence eliminates the use of pyridine. In this method HCN is trapped on both the Cambridge Filter Pad, then extracted with aqueous sodium hydroxide solution, and in an impinger containing the same solution. The solution thus extracted is oxidised to cyanogen chloride by Chloramine-T and treated with coupling reagent, the resulting stable chromophore was measured colorimetrically at 600 nm. The regression equation was linear in the range of 1 to 25 μg/mL for cyanide with a correlation coefficient (R2) > 0.9998. The limit of detection (LOD) was 0.76 μg/cig and the overall relative standard deviation (RSD) of the method was less than 10%. Excellent recoveries of cyanide were obtained in the range from 92% to 112% and the HCN yields from the Kentucky Reference Cigarette 3R4F obtained from the newly developed method are in good agreement with those from the conventional KCN method. The proposed method is robust, reliable, selective and safer than any of the existing methods for determination of hydrogen cyanide in mainstream as well as in sidestream cigarette smoke.

Open access